Bought mine in May 2014. After about a year of daily use, the left button double clicks even if clicked once. VERY ANNOYING!! It is a proven problem in this product, not many are sold in India but if you read the reviews on amazon.com, there are many complaints for this issue.So, if you buy it ensure that you get a warrantee replacement just before it expires, that way it will last (at least) two years!

You need some time to get used to the grip and button functions. But once that is done, it is a great trackball. It also has the scroll key along with page-up/down buttons. You can configure the use of all buttons using the SetPoint application by Logitech. Being wireless, it gives you a lot of flexibility in positioning the device.I have been using the wired Logitech Trackball (Marble Mouse) for many years. The problem was that there was no scroll key. And handling the wires is a headache. This product takes care of all those problems.Only drawback is, it is difficult to carry in your laptop bag as there is no safety case included and buying the case separately costs over 2000 rupees. You cannot directly put it in the bag as there will be no protection against bumps and this may cause the trackball to come out of the socket. Despite this, it's a great product. Highly recommended for right-handed users.

Amazing Mouse. It gives you a good control of working as well as gaming. The track ball takes your experience into an old era and very smooth progressions on the screen.You don't have to drag this mouse to extreme ends to move the mouse cursor across. The Track Ball does this magic. The Mouse remains stationary and the cursor is controlled by the trackball. Everything is good about this mouse. Along with the mouse I got a Duracel AAA battery which I am using since about 3 months now, and it is still performing good. Ofcourse, I turn off the mouse power button at the bottom when I am done using it or when I am moving away from the desk for a long time. This saves a lot of battery.

My only advice is that give the mouse a chance. You may take a week or three to get your muscle memory familiarised with the trackball and the feel of the mouse in general, but once you have gotten a hold of it, it works like charm. Speed, precision, and comfort at its best. Honestly, after the first week of using it, I almost felt like selling it online and going for another option, but then I thought of using it for another week and since then I cannot go about my work without this beast.I am a designer and my work generally includes a lot drag & drop, pixel precision, frequent switching of multiple tabs and a lot of scrolling. Most of these can be easily customised (thanks to the extra mouse buttons) through the Logitech software and it works well with my MacBook Pro. The reason I switched from the regular mouse to this one was to reduce the amount of hand/wrist movements and be able to work from anywhere, irrespective of the type of surface. It's been a month of usage, and the mouse has served well!

Works great as an unified unit with a wireless Logitech keyboard using one USB port. Quality product. But best to check if it suits your hand size and shape, otherwise you may find it difficult to control the trackball. Like many advanced products, the design in made to suit key international populations. South Asian physical feature may differ on average. For me, the thumb tip stretches well beyond the trackball in the normal position and that makes controlling the trackball a little difficult. Your mileage may vary, so best to check it out.